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 * (b) any piece of software and/or hardware listed in the lrgrwrks.txt file if
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package com.oracle.truffle.jx.nodes.interop;

import com.oracle.truffle.api.dsl.Cached;
import com.oracle.truffle.api.instrumentation.StandardTags;
import com.oracle.truffle.api.interop.InteropLibrary;
import com.oracle.truffle.api.interop.TruffleObject;
import com.oracle.truffle.api.interop.UnknownIdentifierException;
import com.oracle.truffle.api.interop.UnsupportedMessageException;
import com.oracle.truffle.api.library.ExportLibrary;
import com.oracle.truffle.api.library.ExportMessage;
import com.oracle.truffle.api.profiles.BranchProfile;
import com.oracle.truffle.api.source.SourceSection;
import com.oracle.truffle.api.strings.TruffleString;
import com.oracle.truffle.jx.runtime.JXStrings;

/** A container class used to store per-node attributes used by the instrumentation framework. */
public abstract class NodeObjectDescriptor implements TruffleObject {

  private final TruffleString name;

  private NodeObjectDescriptor(TruffleString name) {
    assert name != null;
    this.name = name;
  }

  public static NodeObjectDescriptor readVariable(TruffleString name) {
    return new ReadDescriptor(name);
  }

  public static NodeObjectDescriptor writeVariable(
      TruffleString name, SourceSection sourceSection) {
    return new WriteDescriptor(name, sourceSection);
  }

  Object readMember(String member, @Cached BranchProfile error) throws UnknownIdentifierException {
    if (isMemberReadable(member)) {
      return name;
    } else {
      error.enter();
      throw UnknownIdentifierException.create(member);
    }
  }

  abstract boolean isMemberReadable(String member);

  @ExportLibrary(InteropLibrary.class)
  static final class ReadDescriptor extends NodeObjectDescriptor {

    private static final TruffleObject KEYS_READ =
        new NodeObjectDescriptorKeys(JXStrings.constant(StandardTags.ReadVariableTag.NAME));

    ReadDescriptor(TruffleString name) {
      super(name);
    }

    @ExportMessage
    @SuppressWarnings("static-method")
    boolean hasMembers() {
      return true;
    }

    @Override
    @ExportMessage
    boolean isMemberReadable(String member) {
      return StandardTags.ReadVariableTag.NAME.equals(member);
    }

    @ExportMessage
    @SuppressWarnings("static-method")
    Object getMembers(@SuppressWarnings("unused") boolean includeInternal) {
      return KEYS_READ;
    }

    @Override
    @ExportMessage
    Object readMember(String member, @Cached BranchProfile error)
        throws UnknownIdentifierException {
      return super.readMember(member, error);
    }
  }

  @ExportLibrary(InteropLibrary.class)
  static final class WriteDescriptor extends NodeObjectDescriptor {

    private static final TruffleObject KEYS_WRITE =
        new NodeObjectDescriptorKeys(JXStrings.constant(StandardTags.WriteVariableTag.NAME));

    private final Object nameSymbol;

    WriteDescriptor(TruffleString name, SourceSection sourceSection) {
      super(name);
      this.nameSymbol = new NameSymbol(name, sourceSection);
    }

    @ExportMessage
    @SuppressWarnings("static-method")
    boolean hasMembers() {
      return true;
    }

    @Override
    @ExportMessage
    boolean isMemberReadable(String member) {
      return StandardTags.WriteVariableTag.NAME.equals(member);
    }

    @ExportMessage
    @SuppressWarnings("static-method")
    Object getMembers(@SuppressWarnings("unused") boolean includeInternal) {
      return KEYS_WRITE;
    }

    @Override
    @ExportMessage
    Object readMember(String member, @Cached BranchProfile error)
        throws UnknownIdentifierException {
      super.readMember(member, error); // To verify readability
      return nameSymbol;
    }
  }

  @ExportLibrary(InteropLibrary.class)
  static final class NameSymbol implements TruffleObject {

    private final TruffleString name;
    private final SourceSection sourceSection;

    NameSymbol(TruffleString name, SourceSection sourceSection) {
      this.name = name;
      this.sourceSection = sourceSection;
    }

    @ExportMessage
    @SuppressWarnings("static-method")
    boolean isString() {
      return true;
    }

    @ExportMessage
    String asString(@Cached TruffleString.ToJavaStringNode toJavaStringNode) {
      return toJavaStringNode.execute(name);
    }

    @ExportMessage
    TruffleString asTruffleString() {
      return name;
    }

    @ExportMessage
    boolean hasSourceLocation() {
      return sourceSection != null;
    }

    @ExportMessage
    SourceSection getSourceLocation() throws UnsupportedMessageException {
      if (sourceSection != null) {
        return sourceSection;
      } else {
        throw UnsupportedMessageException.create();
      }
    }
  }
}
